In control systems for controlling and/or monitoring an industrial process, the operator typically controls/monitors the entire process or different parts of the process by means of one or more user interfaces (UIs), for example constituted by one or more graphic windows displayed on a display screen, each graphic window displaying process graphics. Such UIs may enable the operator to monitor the status of the different components of the process and/or control the operation of individual components of the process by means of user input provided to the UI. Providing user input to the UI may for example comprise providing instructions to a component of the process by means of a pointing device, such as a computer mouse, for manipulating objects in the UI. For example, appropriate parts in a graphic window displayed on a display screen may be selected and manipulated by means of ‘clicking’ them using the computer mouse.
A UI such as described above may be adapted to visually indicate to the user or operator the positions of the components included in the process relatively to each other. Thus, the UI may provide a display of a schematic arrangement of the components for providing the user with an overview of the process or a part of the process.
In some applications the number of parts or components in the process may be so large that all parts of the process cannot feasibly be shown to the user via a single UI at a time, for example in a single graphic window displayed on a display screen displaying process graphics. Hence, several UIs, or sub-UIs, i.e. UIs that are encompassed by or comprised in another ‘main’ UI, may be required in order to enable controlling and/or monitoring the entire process, but all of these UIs may not feasibly fit within the display screen at the same time. Therefore, in such a case the operator typically alternates between different UIs depending on which part of the process the operator wants to interact with or check status of.
For facilitating navigation between a relatively large number of different UIs comprising graphic windows displayed on a display screen, and also for providing the user with an overview of the entire process, thumbnails of the different graphic windows can be used, i.e. reduced size versions of the graphic windows or parts of them. Such thumbnails are typically displayed on the display screen. By selecting one of the thumbnails on the display screen, the user may bring up or put focus on the graphic window corresponding to the selected thumbnail, and then control and/or monitor the parts of the process indicated on the graphic window that has been brought up or put focus on.
However, even with the provision of such thumbnails, there is generally no user-intuitive manner in which the operator can navigate between different parts of the process using thumbnails that is consistent for different applications, e.g., control systems for different industrial processes. The navigation between different parts of the process in the UI of the process control system may accordingly become time-consuming and/or frustrating for the user.
It may become difficult for a user to get an adequate overview of the entire process since all of the thumbnails may not be displayed at the same time and/or in the same display.
For selecting the correct graphic window to be brought up or to put focus on, the user generally needs to recognize the schematic arrangement of the components in the thumbnail, since the user is in general familiar with the general appearance of the UIs on the display screen. However, reducing the size of a UI comprising a graphic window on the display screen may result in a thumbnail comprising a relatively small graphic object that is cluttered with graphics objects. This may make it difficult for the user to recognize any distinctive pattern in the thumbnail for recognizing which part or parts of the process that are indicated in the UI that corresponds to the thumbnail. This may particularly be the case when the number of different parts or components indicated in the graphic window of the UI is relatively large.